Automatic disconnecting mechanism for fluid pressure operated linkage



June 4, 1957 F. M. DELANY AUTOMATIC DIscoNNEcTING MECHANISM FOR FLUID PRESSURE OPERATED LINKAGE Filed Feb. 24, 195e INVENTOR. FRANK M. DE LANY C ATTORNEY manually openable.

United States Patent .t

AUTOMATIC DiiSCONNECTING MECHANISM FOR FLUID PRESSURE OPERA'IED'LINKAGE Frank M. Deiany, Summit, N. J., assigner to National Pneumatic Co., Inc., Boston, Mass., a corporation of Delaware Application February 24, 1956, Serial No. 567,617

20 Claims. (Cl. 268-30) The present invention relates to an arrangement by means of'which a linkage Apowered by a lluid pressure motor and connecting that motor to an operated device is 'automatically disconnected upon the -release of'operative pressure in or'to that motor, thereafter permitting manual movement of the device entirely independently of the motor.

The invention has general application to all systems in which a device is operated by a tluid pressure motor and in which, upon failure of the motor or for any other reason, manual operation of the device is desired. If the device should remain operatively connected to the motor such manual operation would necessitate movement of the motor piston within its cylinder, thus unduly restricting freedom of movement of the device. VIn accordance with the present invention the disconnection of the device from the motor permits it to be manually moved freely and readily without in any way alecting Ythe motor.

The invention is here specifically illustrated as part of a linkage by means of which a uid pressure motor, and more specilically such a motor of the differential piston type, is adapted to move doors between open and closed positions. This type of system is often employed in railroad passenger cars =and the like, the trains in which those cars are coupled usually being provided with va central control by means of which the conductor or other appropriate official can control the opening and closing of the train doors. Occasionally cars equipped with door opening systems of this type are coupled with cars not thus equipped, and in such a case it is desired that the doors of all of the cars be manually opened and closed. In other instances the power source tothe motors may fail, 'and then there is no alternative but to have the doors In either event it would be a complicated and time consuming matter for a member of the train or maintenance crew to gain access to each individual motor and disconnect it from the door or doors which it is normally designed tooperate. Moreover,ithe

possibility of such personnel forgetting to disconnect a particular motor or motors cannot be overlooked.

In accordance with the present inventionthe linkage between the motors and the doors is so constructedthat so long as the motors are operative, so long as pressure is Vapplied to the motors, the motors and doors will beoperatively connected. However, upon release of the pressure applied y.to the motors for any reason, whether because of malfunction of the system or purposefully, the linkage between the motors and their respective doors willautomatically be released so that the doors are freeto .move independently of the motor pistons.

.This result is accomplished'by means of sturdy and ef- Vfective .mechanism which is substantially foolproof Vin operation, which is Well capable of withstanding the stresses. and strains to which it will be subjected While. in use, and which will provide for establishment of the operative connection between the motors and theV doors no matter what the relative positions ofthe motors -and doors might beat the time that the motors are powered.

'It is merely necessary, once pressure has been applied to ice . 2 themotors, to run 4the motors through aV single operating cycle, at the end of which all of the motor-door operative connections will be established.

To the accomplishment of the above, and to such other objects as may hereinafter appear, the present invention relates to the arrangement of a linkage between auid pressure motor and an operated device,-as dened in the appended claims and as described in Ithis specilication, taken together with the accompanying drawings, in which:

'.Fig. 1 is a side elevational view of one embodiment of the present invention, the parts being shown inthe position which they assume when the door is opened while the `operative connection between the door and motor is established;

Fig. 2 is a crossY sectional view taken along the line '2 2 ofV Fig. 1 on an enlarged scale, of a portion of that koperatively connected bymeansof a linkage generally designated 4 to some suitable operated device such as one or more doors of va railroad car (not shown). The motor l2, in the form here specifically disclosed, is of the conventional differential piston type, and comprises a'cylin- Y'der having a large section 6a and a small section 6b, the

cylinder being mounted at one end on an appropriate'supporting post 8. The mounting is here shown as pivotal, --but that ,is by no means essential to the operation of the device. The motor 2 is provided with a large piston 10a slidable in the cylinder section 6a and a small piston'lb slidable in the small cylindersection 6b, the pistons being connected by a large diameter rod 12 which is, however, somewhat smaller than the internal diameter of the cylindersection 6b. Means generally designated 14 are provided for exerting a substantially constant pressure yin the space between the pistons 10a and 10b. A second means -generally designated 16 is providedfor selectively applying or releasing pressure within the cylinder section 6a to the right ofthe largek piston 10a. As is-conventional inthe operation of motors of this type, pressure exerted withinthe cylinder section aon the right hand side of the piston 10a will overcome the pressure exerted on the left hand side of the piston 10a because of the greater eiectve area on the right vhand side of the piston 10a as .compared with theY left vhandside thereof. Consequentlythe pistons 10a and 10b and the rod 12 will Vmove to the left to thevposition shown in broken lines shown in Fig. l. When pressure is Ireleased from the cylinder section 6a the pressure active on the left hand side of the p1ston 10a will move the pistons 10a and 10b and the rod 12 back to the right.

A p1ston rod 18 extends out to the left from the piston 10b and a cylinder 20 is secured thereto, as by means :of the adapter nut 22 which is externally threadedly received on the threaded exterior of the piston rod 18.

The pistonrod 181 ist provided with a passage 24 one end -of which opens onto the interior ofthe cylinder 20 and yexerted-within the cylinder sectionb via themeans 14 .will also bel exerted inside' the ,cylinder .20.

The left hand endof the .cylinder :20 is internally Y rthreaded at 26 and :a plug 228;'is ithreadedly :received therein and projects out therefrom, the external diameter 'of the plug 23, as'here disclosed, being substantially the same as the external diameter of the cylinder 20. VThe left hand end of the plug 28 is slotted, at 30, and a pair of connectormembers 5241, V32b rare pivotally mounted ewithin the slot on pinsj34a 1and"34b' respectively 'These connectormembers34a and fibareprovideld'with ,iingers 36a and Sb within theslots. 3-9 andwhich overlap one another substantiallyin-line vwiththe axis of the lplug 2S. The connectormembers 32dV and 325, on'the [other side ofthe piston pins aand 34h respectively,

extend out axially beyond the plug 28 and are provided with outwardly extending projecting portions 38a and SSI) respectively. A spring 40 is 'operatively connected-between the connector members 32a and 32b to the left ofthose pivotal axes 34a and 34]; respectively, the spring 4? being active to pivot the connector members 32a and 32h counter-clockwise and clockwise respectively to the position shown iti-Fig. 3, in which the projecting portions .'SSaiand 3850i the connector members 32a and 321; re-

spectiveiy are radially withdrawn. f

Siidable within the cylinder is a piston 42; AA spring itis positioned between the piston #i2 and the plug 28,

that spring being of the compression type and normally moving the piston 42'to theright as shown in Fig. 3.

Upon the application of iiuid pressure within the cylinder 2i), however, the piston 42 will be moved to the `left to the position shown in Fig. 2, compressing the spring 44. A rod 46 is secured-to the piston 42 and movestherewith, the plug 28'being provided with a passage 48 through which the rod 45 is slidable, Vthe lefthand end of the passage 43 opening onto the slot 30 in line with the overlapped ends 36a and 36h of the connector members 32arand 32]) respectively. VAs may clearly be seen from .Fig 2, when the piston 42 is moved to the left the rod 46 moves therewith so that its tip extends out from the passage 48 into the slot 3&3 where it engages the overlapping connector member ngers 36a and 36b and, in continuing to move to theleft, causes the connector members. 32a and 32b to pivot in clockwise and counterclockwise directions respectively from their positions shown in Fig. 3, thus causing the projecting portions 38a 'and 38]; thereof to extend radially out beyond the pe- .'riphery of the plug 2S.

A tube Si) is slidable over the plug 2S and is provided Y with an internal groove 52 into which the projecting por- Vwill be applied within the cylinder 2t), the piston 42l will bemoved to'the left, and the projecting portions 38a and 38h of the connector members 32a and 32b respectively will be received within kthe groove 52 in the tube 50. Hence there will be a direct and positive mechani- 'cal connection between the motor pistons a and 10b andthe device to be operated. The application-or yrelease of pressure within theV cylinder part 6a will cause the motor pistons .wat and itil;y to move to the left or right respectively, thus giving rise to corresponding movement of the operated device, for example, causing the Y doors to open and close respectively.

if pressure should fail within the cylinder section 6b, either because of malfunction of the pressure system or purposefully, as when a railroad car is connected in a train with other cars not having power operated doors, the pressure appliedwithin cylinder20 will also fail. The spring 44 will then 'move the piston 42 to thel right Vto the position shown in Pig. 3, the spring will cause the will ride along the inner surface of the tube 5t) until they come into registration with the internal groove 52, and

the motor pistons 10a and 10b will be broken;

. 4 thus the mechanical connection between the tube and The tube St) will then be freely slidable over the plug 23 Vand the cylinder 2) in the direction of the arrows 56 of Figs. l and 3, Fig. l showing in broken lines the position which the tube 5d may assume when, for example, the doors to which it is connected'are' manually opened while the pistons 10a and lb and the cylinder 20 remain in their position shown in Fig. l. VAs a result the operated device, such as the door, may be manually opened and closed without havingV to'move the motor pistons 10a and 10b.

It may be noted that even if the spring 44 should fail the action of the spring 4t) will be suicient to withdraw the projectingportions 33a and 38h of the conneetor members 32a and 3211 respectively from the groove S2, and in so doing will move the rod i6 to the right,

since there willno longer-be any appreciable pressure Awithin Vthe cylinder 2th resisting that movement;

Upon the renewedexertio'n of pressure within the cylin- .der part 6b the piston 42 will again be urged to the left to its position shown in Fig. 2. Ifthe tube 59 is not then in such a position astopermitthe connector member projecting parts 38a and 38b to enter the groove 52,

.those parts will be urged against the inner surface of the tube Si). .of its pistonsY 16a and itb will cause a corresponding If the motor 2 is once cycled the movement Amovement of the cylinder 20 and the plug 23, the latter carrying with it the connector members 32a and 32b. The projecting connector'member portions 33a and Sbb they will then snap into that groove, thus re-establishing Ythe direct operative connection between themotor 2 and the operated device.

`While in the construction lhere specifically disclosed pressure communicating between the cylinder 2@ and the motor cylinder section 6b Vis accomplished by means of the passage 24 through the piston rod i8, such pressure communication can be established in any other appropriate way, as through the use of an external connection, flexible or otherwise, between the cylinders 6b and 2t), between the cylinder 2t) and the pressure means 14 which communicates with the motor cylinder section 6b, or even directly between the cylinder 2t? and the source of pressure for the motor cylinder section 6b. However, certain definite and obvious advantages as to reliability and positiveness of operation inhere in the direct connection Vof the cylinder 2i) to the piston rod 18 and the provision of the communicating passage 24 in the piston rod 18.

It will be seen from the above that the specilic construction here disclosed is simple and sturdy, may readily be assembled, andadds but little to the overall expenseof the linkage. However, it will be apparent that many variations may be made therein, all within the spiritY of the invention as defined in the following claims.

I claim:

l. In the combination of a fluid pressure motor having a cylinder within which pressure is exerted and a piston therein, an operated device, and a linkage operatively connecting said piston and said device; the improvement which comprises said linkage comprising a cylinder within which a second piston is movable, biasing meansfor urging said second piston in one'direction therein, the'application of iiuid pressure Ywithin said cylinder moving said second piston in the other direction against theaction of said biasing means, a'pressure connection between said Vmotor cylinder and vsaid linkage cylinder through which Y 4iuid pressure may pass, thereby applying` pressure within said linkage cylinder when pressuremis exerted insaid motor cylinder, a detachablehconnection Vbetween' said linkage cylinder and the remainder of said linkage actuatable between detachingrrand attaching conditions, and an operative connection between said detachable connection 'agree-,tese

vis is in one of its biased and iiuid pressure moved positions to actuate said connection to its detached condition, thus operatively separating said device from said motor, and eective when said second piston is in the other of its biased and luid pressure moved positionsy to actuate said connection to its attaching condition, thusoperatively connecting said device to said motor.

2. The combination of claim l, in which said detachable connection comprises a nrst member connected to said linkage cylinder, a second member movable relative to said first member, a locking member carried by said first member and movable between operative and inoperative positions in which it respectively lockingly engages and disengages from said second member, and an operative connection between said locking member and said second piston etective to move said locking member to its operative and inoperative positions respectively when said second piston is in one and the other of its fluid pressure moved and biased positions respectively.

3. The combination of claim 2, in which said operative connection between said locking member and said second piston comprises a'rod operatively connected to said second piston, said first memberhaving a passage therethrough through which said rod'slides and beyond which said rod is movable, said lockingA memberbeing carried by said irst member beyond said passage, said rod engaging said locking member and moving it to operative position when said rod is slid out hom said passage.

4. The combination ofclaim 2, in which saidoperative connection between said lockingV member and said second piston comprises a rod operatively connected to said second piston, said irst member vhaving a passage therethrough through which said rod slides and beyond which said rod is movable, said locking member being carried 'by said iirst member beyond said passage, said rod engaging said locking member and moving it to operative position when said rod is slid ont from said passage, and biasing means urging said` locking member to its inoperative position.

5. The combination of claim l, in which said 'detachable connectioncomprises a iirst member connectedvto said linkage cylinder, a second .member slidable over said Vfirst member and having a recess on its innersurface, a

locking member articulatelymounted on said iirst member and movable between an operative position in which it is received within said recess in said second member, thereby connecting saidrstand second members for simultaneousY movement, and an inoperative position withdrawn from said recess in said second member, thereby releasing said second member for movement independently of said irst member, and an operative connection between said locking member and said second piston eiective to move said locking member to its operative and inoperative positions respectively when said second piston is in one and the other of its fluid pressure moved and biased positions respectively.

6, The combination of claim 5, in which said operative connection between said locking member and said second piston comprises a rod operatively connected to said second piston, said irst member having a passage therethrough through which said rod slides and beyond which said rod is movable, said locking member being carried by said first member beyond said passage, said rod engaging said locking member and moving it to operative position when said rod is slid out from said passage.

7. The combination of claim 5, in which said operative connection between said locking member and said second piston comprises a rod operatively connected to said second piston, said first member having a passage therethrough through which said rod slides and beyond which said rod is movable, said locking member being carried by said rst member beyond said passage, said rod engaging said locking member and moving it to operative position when said rod is slid out from said passage, and

biasing means urging said locking `member to lits inoperative fp osition.

8. In the combination of a fluid pressure motor having a vcylinder within which pressure is exerted and a piston and piston rod therein, an operated device, `and a linkage operatively connecting said-piston rod and said device; the improvement which. comprisesja cylinder connected to said piston rod ywithin which a second piston is movable, ybiasing means for urging said `second piston in one direction therein toward said piston rod, the application of fluid pressure within said cylinder moving said second piston in the other direction against the action of said biasing means, a pressure connection between said motor connection lto its detached condition, thus operatively separating said device from said motor, land effective when said second piston is in the other of its biased and iiuid pressure moved positions to actuate said connection to its attaching condition, vthus operatively connecting said device to said mot-or.

9. The combination of cl-airn 8, in which said detachable connection comprises a iirst member connected to said linkage cylinder, a second member movable relative to said first member, a locking member carried by said first member and movable between operative and inoperative positions in which it respectively lockingly engages -and disengages from `said second member, and an operative connection between said locking member and said second piston eective to move said locking member to its 4operative and inoperative positions respectively when said second piston is on oneand the other Iof its fluid pressure moved and biased positions respectively.

10. The combination of claim 9, in which said operative connection between said locking member and said second piston comprises 'a rod operatively connected to said second piston, saidirst member having a passage therethrough through which said rod slides and beyond vwhich said -rod is movable, said locking member being carried by said first member beyond :said passage, said rod engaging said locking member and moving it to operative position when said rod is slid out lfrom said passage.

11. The combination of claim 9, in which said operative connection between said locking member and said second piston comprises a rod -operatively connected to said second piston, said first member having a passage therethrough through which said rod slides and beyond which said rod is movable, said locking member being carried by said lirst member beyond said passage, said rod engaging said locking member and moving it to operative position when said rod is slid out from said passage, and biasing means urging said locking member to its inoperative position.

12. The combination of claim 8, in which said detachable connection comprises a iirst member connected to said linkage cylinder, a second member slidable over said iirst member and having a recess on its inner surface, a locking member articulately mounted on said first member and movable between Ian operative position in which tit is Ireceived within said recess in said second member, thereby connecting said first and second members for simultaneous movement, and an inoperative position withdrawn from said recess in said second member, thereby lreleasing said second member for movement independently of said rst member, and an Ioperative connection .accordance with the position of said between 'said locking member and sai-d second piston effective to move said locking member to its operative :and inoperative i positions' respectively when said second pressure moved yrod engaging said locking member yand moving it to operative position when said rod is slid out from said'passage.

14. The combination Aof claim 12, in which said Voperative connection between said locking member and said second piston comprises a rodV operatively connected to said second piston, said rst member having a passage therethrough through which said'rod slides and beyond which said rod is movable, said locking member being carried by said first member beyond said'passage, said Vrod engaging said locking member and moving it to operative position when said rod is slid out from said passage, and biasing means urging said locking member to its inoperative position.

15. In combination, a uid pressure motor having a cylinder within which pressureris exerted, and a piston rod extending out therefrom, -a second cylinder operatively connected to said piston rod to move therewith, a piston movable withinV said second cylinder, said motor piston rod having a passage communicating between said motor cylinder and said second cylinder, through Which passage uid pressure is transmitted, means Iactive on said piston in said second cylinder to urge it in one direction, the application of duid pressure in said second cylinder via said passage moving said piston in the opposite direction, a connector member articulately mounted on said second vcylinder and movable between rstrand second positions thereon, and an operative connection 'between said connector member and said piston, whereby the former is moved to its irst and second positions respectively in piston within said second cylinder. Y

16. In combination, a Vfluid pressure motor having a cylinder within which pressure is exerted and la piston rod extending out therefrom, a second cylinder operatively connected to said piston rod and movable therewith, a piston movable in said second cylinder toward and Ifrom said piston rod, said piston rod having a passage'c'ommunicating between said motor cylinder and said second cylinder at the piston rod end of the latter, through which passage fluidpressure is transmitted, spring means active Yori-said piston rod, the application of uidpressure in said second cylinder at the piston rod end thereof moving said pistoninV the opposite direction, the end of said second cylinder remote from said piston rod carrying a vconnector member pivotally mounted thereon, said latter cylinder end having a passage therethrough, said piston having an element connected thereto and movable through said passage, said connector member having a Vpart displaced from its pivotal axis `and in line with said passage and operatively connected to said element, where- Vby movement of said piston results in movement of said connector member.

17. The combination of claim 15, in which said Huid pressure motor is of the differential piston type, the cylinder thereof being divided into two sections in the iirst of which pressure is constantly applied and in the second of which pressure is intermittently applied to cause movement of said motor piston rod, said piston rod passage communicating between said second cylinder and said first section of said motor cylinder.

18. The combination of claim 16, in which said uid pressure motor is of the differential piston type, the cylinder thereof `being divided into two sections in the rst of which pressure is constantly applied and in the second of Vwhich pressure is intermittently applied to cause movement of said motor piston rod, said piston rodvpassage Ycommunicating between said second cylinder and said rst section of said motor cylinder.

19. The combination of claim l, in which said uid pressure motor is of the differential piston type, the cylin- VVsection of said motor cylinder.

20. The combination of claim 8, in which said uid pressure motor is of the differential piston type, the cylinder thereof being divided into two sections in the rst of Vwhich pressure is constantly applied and in the second of which pressure is intermittently applied to cause movement of the said motor piston rod, said piston rod passage communicating between said linkage cylinder and said rst section of said motor cylinder.

No references cited. 

